895 lines
35 KiB
Nim
895 lines
35 KiB
Nim
# beacon_chain
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# Copyright (c) 2022 Status Research & Development GmbH
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# Licensed and distributed under either of
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# * MIT license (license terms in the root directory or at https://opensource.org/licenses/MIT).
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# * Apache v2 license (license terms in the root directory or at https://www.apache.org/licenses/LICENSE-2.0).
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# at your option. This file may not be copied, modified, or distributed except according to those terms.
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{.push raises: [Defect].}
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# This implements the pre-release proposal of the libp2p based light client sync
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# protocol. See https://github.com/ethereum/consensus-specs/pull/2802
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import
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# Status libraries
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stew/[bitops2, objects],
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# Beacon chain internals
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../spec/datatypes/[phase0, altair, bellatrix],
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../beacon_chain_db_light_client,
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"."/[block_pools_types, blockchain_dag]
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logScope: topics = "chaindag"
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type
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HashedBeaconStateWithSyncCommittee =
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bellatrix.HashedBeaconState |
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altair.HashedBeaconState
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TrustedSignedBeaconBlockWithSyncAggregate =
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bellatrix.TrustedSignedBeaconBlock |
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altair.TrustedSignedBeaconBlock
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template nextEpochBoundarySlot(slot: Slot): Slot =
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## Compute the first possible epoch boundary state slot of a `Checkpoint`
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## referring to a block at given slot.
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(slot + (SLOTS_PER_EPOCH - 1)).epoch.start_slot
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proc updateExistingState(
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dag: ChainDAGRef, state: var ForkedHashedBeaconState, bsi: BlockSlotId,
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save: bool, cache: var StateCache): bool =
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## Wrapper around `updateState` for states expected to exist.
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let ok = dag.updateState(state, bsi, save, cache)
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if not ok:
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error "State failed to load unexpectedly", bsi, tail = dag.tail.slot
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doAssert verifyFinalization notin dag.updateFlags
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ok
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template withUpdatedExistingState(
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dag: ChainDAGRef, stateParam: var ForkedHashedBeaconState,
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bsiParam: BlockSlotId, okBody: untyped, failureBody: untyped): untyped =
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## Wrapper around `withUpdatedState` for states expected to exist.
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block:
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let bsi = bsiParam
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dag.withUpdatedState(stateParam, bsiParam) do:
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okBody
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do:
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error "State failed to load unexpectedly", bsi, tail = dag.tail.slot
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doAssert verifyFinalization notin dag.updateFlags
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failureBody
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proc getExistingBlockIdAtSlot(dag: ChainDAGRef, slot: Slot): Opt[BlockSlotId] =
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## Wrapper around `getBlockIdAtSlot` for blocks expected to exist.
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let bsi = dag.getBlockIdAtSlot(slot)
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if bsi.isErr:
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error "Block failed to load unexpectedly", slot, tail = dag.tail.slot
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doAssert verifyFinalization notin dag.updateFlags
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bsi
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proc existingParent(dag: ChainDAGRef, bid: BlockId): Opt[BlockId] =
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## Wrapper around `parent` for parents known to exist.
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let parent = dag.parent(bid)
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if parent.isErr:
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error "Parent failed to load unexpectedly", bid, tail = dag.tail.slot
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doAssert verifyFinalization notin dag.updateFlags
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parent
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proc getExistingForkedBlock(
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dag: ChainDAGRef, bid: BlockId): Opt[ForkedTrustedSignedBeaconBlock] =
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## Wrapper around `getForkedBlock` for blocks expected to exist.
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let bdata = dag.getForkedBlock(bid)
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if bdata.isErr:
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error "Block failed to load unexpectedly", bid, tail = dag.tail.slot
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doAssert verifyFinalization notin dag.updateFlags
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bdata
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proc existingCurrentSyncCommitteeForPeriod(
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dag: ChainDAGRef,
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tmpState: var ForkedHashedBeaconState,
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period: SyncCommitteePeriod): Opt[SyncCommittee] =
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## Wrapper around `currentSyncCommitteeForPeriod` for states known to exist.
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let syncCommittee = dag.currentSyncCommitteeForPeriod(tmpState, period)
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if syncCommittee.isErr:
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error "Current sync committee failed to load unexpectedly",
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period, tail = dag.tail.slot
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doAssert verifyFinalization notin dag.updateFlags
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syncCommittee
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template syncCommitteeRoot(
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state: HashedBeaconStateWithSyncCommittee): Eth2Digest =
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## Compute a root to uniquely identify `current_sync_committee` and
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## `next_sync_committee`.
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withEth2Hash:
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h.update state.data.current_sync_committee.hash_tree_root().data
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h.update state.data.next_sync_committee.hash_tree_root().data
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proc syncCommitteeRootForPeriod(
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dag: ChainDAGRef,
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tmpState: var ForkedHashedBeaconState,
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period: SyncCommitteePeriod): Opt[Eth2Digest] =
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## Compute a root to uniquely identify `current_sync_committee` and
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## `next_sync_committee` for a given sync committee period.
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## For non-finalized periods, follow the chain as selected by fork choice.
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let lowSlot = max(dag.tail.slot, dag.cfg.ALTAIR_FORK_EPOCH.start_slot)
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if period < lowSlot.sync_committee_period:
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return err()
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let
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periodStartSlot = period.start_slot
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syncCommitteeSlot = max(periodStartSlot, lowSlot)
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bsi = ? dag.getExistingBlockIdAtSlot(syncCommitteeSlot)
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dag.withUpdatedExistingState(tmpState, bsi) do:
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withState(state):
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when stateFork >= BeaconStateFork.Altair:
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ok state.syncCommitteeRoot
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else: raiseAssert "Unreachable"
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do: err()
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proc initLightClientDataStore*(
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config: LightClientDataConfig,
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cfg: RuntimeConfig,
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db: LightClientDataDB): LightClientDataStore =
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## Initialize light client data store.
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LightClientDataStore(
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db: db,
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serve: config.serve,
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importMode: config.importMode,
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maxPeriods: config.maxPeriods.get(cfg.defaultLightClientDataMaxPeriods),
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onLightClientFinalityUpdate: config.onLightClientFinalityUpdate,
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onLightClientOptimisticUpdate: config.onLightClientOptimisticUpdate)
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func targetLightClientTailSlot(dag: ChainDAGRef): Slot =
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## Earliest slot for which light client data is retained.
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let
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maxPeriods = dag.lcDataStore.maxPeriods
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headPeriod = dag.head.slot.sync_committee_period
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lowSlot = max(dag.tail.slot, dag.cfg.ALTAIR_FORK_EPOCH.start_slot)
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tail = max(headPeriod + 1, maxPeriods.SyncCommitteePeriod) - maxPeriods
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max(tail.start_slot, lowSlot)
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func handleUnexpectedLightClientError(dag: ChainDAGRef, buggedSlot: Slot) =
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## If there is an unexpected error, adjust `tailSlot` to keep track of the
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## section for which complete light client data is available, and to avoid
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## failed lookups of cached light client data.
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doAssert verifyFinalization notin dag.updateFlags
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if buggedSlot >= dag.lcDataStore.cache.tailSlot:
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dag.lcDataStore.cache.tailSlot = buggedSlot + 1
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proc initLightClientBootstrapForPeriod(
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dag: ChainDAGRef,
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period: SyncCommitteePeriod): Opt[void] =
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## Compute and cache `LightClientBootstrap` data for all finalized
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## epoch boundary blocks within a given sync committee period.
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if not dag.isNextSyncCommitteeFinalized(period):
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return ok()
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if dag.lcDataStore.db.isPeriodSealed(period):
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return ok()
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let startTick = Moment.now()
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debug "Caching historic LC bootstrap data", period
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defer:
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let endTick = Moment.now()
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debug "Historic LC bootstrap data cached", period,
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cacheDur = endTick - startTick
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let
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periodStartSlot = period.start_slot
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periodEndSlot = periodStartSlot + SLOTS_PER_SYNC_COMMITTEE_PERIOD - 1
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lowSlot = max(periodStartSlot, dag.targetLightClientTailSlot)
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highSlot = min(periodEndSlot, dag.finalizedHead.blck.slot)
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lowBoundarySlot = lowSlot.nextEpochBoundarySlot
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highBoundarySlot = highSlot.nextEpochBoundarySlot
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var
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res = ok()
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tmpState = assignClone(dag.headState)
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tmpCache: StateCache
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nextBoundarySlot = lowBoundarySlot
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while nextBoundarySlot <= highBoundarySlot:
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defer: nextBoundarySlot += SLOTS_PER_EPOCH
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let
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bsi = dag.getExistingBlockIdAtSlot(nextBoundarySlot).valueOr:
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dag.handleUnexpectedLightClientError(nextBoundarySlot)
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res.err()
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continue
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bid = bsi.bid
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boundarySlot = bid.slot.nextEpochBoundarySlot
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if boundarySlot == nextBoundarySlot and bid.slot >= lowSlot and
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not dag.lcDataStore.db.hasCurrentSyncCommitteeBranch(bid.slot):
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if not dag.updateExistingState(
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tmpState[], bid.atSlot, save = false, tmpCache):
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dag.handleUnexpectedLightClientError(bid.slot)
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res.err()
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continue
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let branch = withState(tmpState[]):
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when stateFork >= BeaconStateFork.Altair:
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state.data.build_proof(altair.CURRENT_SYNC_COMMITTEE_INDEX).get
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else: raiseAssert "Unreachable"
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dag.lcDataStore.db.putCurrentSyncCommitteeBranch(bid.slot, branch)
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res
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proc initLightClientUpdateForPeriod(
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dag: ChainDAGRef, period: SyncCommitteePeriod): Opt[void] =
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## Compute and cache the best `LightClientUpdate` within a given
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## sync committee period up through the finalized head block.
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## Non-finalized blocks are processed incrementally by other functions.
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if not dag.isNextSyncCommitteeFinalized(period):
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return ok()
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if dag.lcDataStore.db.isPeriodSealed(period):
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return ok()
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let startTick = Moment.now()
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debug "Computing best historic LC update", period
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proc logBest(endTick = Moment.now()) =
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# Using a helper function reduces code size as the `defer` beneath is
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# replicated on every `return`, and the log statement allocates another
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# copy of the arguments on the stack for each instantiation (~1 MB stack!)
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debug "Best historic LC update computed",
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period, update = dag.lcDataStore.db.getBestUpdate(period),
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computeDur = endTick - startTick
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defer: logBest()
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proc maxParticipantsBlock(
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dag: ChainDAGRef, highBid: BlockId, lowSlot: Slot
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): tuple[bid: Opt[BlockId], res: Opt[void]] =
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## Determine the earliest block with most sync committee signatures among
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## ancestors of `highBid` with at least `lowSlot` as parent block slot.
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## Return `err` if no block with `MIN_SYNC_COMMITTEE_PARTICIPANTS` exists.
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## `res` in result indicates whether no unexpected errors occurred.
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var
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maxParticipants = MIN_SYNC_COMMITTEE_PARTICIPANTS
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maxBid: Opt[BlockId]
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res = Opt[void].ok()
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bid = highBid
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while true:
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if bid.slot <= lowSlot:
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break
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let parentBid = dag.existingParent(bid).valueOr:
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dag.handleUnexpectedLightClientError(bid.slot)
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res.err()
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break
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if parentBid.slot < lowSlot:
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break
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let
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bdata = dag.getExistingForkedBlock(bid).valueOr:
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dag.handleUnexpectedLightClientError(bid.slot)
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res.err()
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break
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numParticipants =
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withBlck(bdata):
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when stateFork >= BeaconStateFork.Altair:
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countOnes(blck.message.body.sync_aggregate.sync_committee_bits)
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else: raiseAssert "Unreachable"
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if numParticipants >= maxParticipants:
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maxParticipants = numParticipants
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maxBid.ok bid
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bid = parentBid
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(bid: maxBid, res: res)
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# Determine the block in the period with highest sync committee participation
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let
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periodStartSlot = period.start_slot
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periodEndSlot = periodStartSlot + SLOTS_PER_SYNC_COMMITTEE_PERIOD - 1
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lowSlot = max(periodStartSlot, dag.targetLightClientTailSlot)
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highSlot = min(periodEndSlot, dag.finalizedHead.blck.slot)
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fullPeriodCovered = (dag.finalizedHead.slot > periodEndSlot)
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highBsi = dag.getExistingBlockIdAtSlot(highSlot).valueOr:
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dag.handleUnexpectedLightClientError(highSlot)
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return err()
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highBid = highBsi.bid
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maxParticipantsRes = dag.maxParticipantsBlock(highBid, lowSlot)
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maxParticipantsBid = maxParticipantsRes.bid.valueOr:
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const update = default(altair.LightClientUpdate)
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if fullPeriodCovered and maxParticipantsRes.res.isOk: # No block in period
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dag.lcDataStore.db.putBestUpdate(period, update)
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else:
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dag.lcDataStore.db.putUpdateIfBetter(period, update)
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return maxParticipantsRes.res
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# The block with highest participation may refer to a `finalized_checkpoint`
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# in a different sync committee period. If that is the case, search for a
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# later block with a `finalized_checkpoint` within the given sync committee
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# period, despite it having a lower sync committee participation
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var
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res = ok()
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tmpState = assignClone(dag.headState)
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signatureBid {.noinit.}, finalizedBid {.noinit.}: BlockId
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signatureBid.slot = FAR_FUTURE_SLOT
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finalizedBid.slot = FAR_FUTURE_SLOT
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while true:
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if signatureBid.slot == FAR_FUTURE_SLOT:
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signatureBid = maxParticipantsBid
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else:
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let
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nextLowSlot = signatureBid.slot + 1
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signatureRes = dag.maxParticipantsBlock(highBid, nextLowSlot)
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if signatureRes.res.isErr:
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res.err()
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signatureBid = signatureRes.bid.valueOr:
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signatureBid = maxParticipantsBid
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break
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let
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attestedBid = dag.existingParent(signatureBid).valueOr:
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dag.handleUnexpectedLightClientError(signatureBid.slot)
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res.err()
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continue
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finalizedEpoch = block:
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dag.withUpdatedExistingState(tmpState[], attestedBid.atSlot) do:
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withState(state):
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when stateFork >= BeaconStateFork.Altair:
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state.data.finalized_checkpoint.epoch
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else: raiseAssert "Unreachable"
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do:
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dag.handleUnexpectedLightClientError(attestedBid.slot)
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res.err()
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continue
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finalizedSlot = finalizedEpoch.start_slot
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finalizedBsi =
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if finalizedSlot >= dag.tail.slot:
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dag.getExistingBlockIdAtSlot(finalizedSlot).valueOr:
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dag.handleUnexpectedLightClientError(finalizedSlot)
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res.err()
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continue
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else:
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continue
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if finalizedBid.slot >= lowSlot:
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finalizedBid = finalizedBsi.bid
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break
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if signatureBid == maxParticipantsBid:
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finalizedBid = finalizedBsi.bid # For fallback `break` at start of loop
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# Save best light client data for given period
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var update {.noinit.}: altair.LightClientUpdate
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let attestedBid = dag.existingParent(signatureBid).valueOr:
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dag.handleUnexpectedLightClientError(signatureBid.slot)
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return err()
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dag.withUpdatedExistingState(tmpState[], attestedBid.atSlot) do:
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let bdata = dag.getExistingForkedBlock(bid).valueOr:
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dag.handleUnexpectedLightClientError(bid.slot)
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return err()
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withStateAndBlck(state, bdata):
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when stateFork >= BeaconStateFork.Altair:
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update.attested_header = blck.toBeaconBlockHeader()
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update.next_sync_committee = state.data.next_sync_committee
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update.next_sync_committee_branch =
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state.data.build_proof(altair.NEXT_SYNC_COMMITTEE_INDEX).get
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if finalizedBid.slot == FAR_FUTURE_SLOT:
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update.finality_branch.reset()
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else:
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update.finality_branch =
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state.data.build_proof(altair.FINALIZED_ROOT_INDEX).get
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else: raiseAssert "Unreachable"
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do:
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dag.handleUnexpectedLightClientError(attestedBid.slot)
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return err()
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if finalizedBid.slot == FAR_FUTURE_SLOT or finalizedBid.slot == GENESIS_SLOT:
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update.finalized_header.reset()
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else:
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let bdata = dag.getExistingForkedBlock(finalizedBid).valueOr:
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dag.handleUnexpectedLightClientError(finalizedBid.slot)
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return err()
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withBlck(bdata):
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update.finalized_header = blck.toBeaconBlockHeader()
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let bdata = dag.getExistingForkedBlock(signatureBid).valueOr:
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dag.handleUnexpectedLightClientError(signatureBid.slot)
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return err()
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withBlck(bdata):
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when stateFork >= BeaconStateFork.Altair:
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update.sync_aggregate = blck.asSigned().message.body.sync_aggregate
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else: raiseAssert "Unreachable"
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update.signature_slot = signatureBid.slot
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if fullPeriodCovered and res.isOk:
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dag.lcDataStore.db.putBestUpdate(period, update)
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else:
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dag.lcDataStore.db.putUpdateIfBetter(period, update)
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res
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proc initLightClientDataForPeriod(
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dag: ChainDAGRef, period: SyncCommitteePeriod): Opt[void] =
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## Import light client data for a given sync committee period.
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if dag.lcDataStore.db.isPeriodSealed(period):
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return ok()
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let
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fullPeriodCovered = (dag.finalizedHead.slot >= (period + 1).start_slot)
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res1 = dag.initLightClientBootstrapForPeriod(period)
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res2 = dag.initLightClientUpdateForPeriod(period)
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if res1.isErr or res2.isErr:
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return err()
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if fullPeriodCovered:
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dag.lcDataStore.db.sealPeriod(period)
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ok()
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proc getLightClientData(
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dag: ChainDAGRef,
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bid: BlockId): CachedLightClientData =
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## Fetch cached light client data about a given block.
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## Data must be cached (`cacheLightClientData`) before calling this function.
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try: dag.lcDataStore.cache.data[bid]
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except KeyError: raiseAssert "Unreachable"
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proc cacheLightClientData(
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dag: ChainDAGRef, state: HashedBeaconStateWithSyncCommittee, bid: BlockId) =
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## Cache data for a given block and its post-state to speed up creating future
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## `LightClientUpdate` and `LightClientBootstrap` instances that refer to this
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## block and state.
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let cachedData = CachedLightClientData(
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current_sync_committee_branch:
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state.data.build_proof(altair.CURRENT_SYNC_COMMITTEE_INDEX).get,
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next_sync_committee_branch:
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state.data.build_proof(altair.NEXT_SYNC_COMMITTEE_INDEX).get,
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finalized_slot:
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state.data.finalized_checkpoint.epoch.start_slot,
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finality_branch:
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state.data.build_proof(altair.FINALIZED_ROOT_INDEX).get)
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if dag.lcDataStore.cache.data.hasKeyOrPut(bid, cachedData):
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doAssert false, "Redundant `cacheLightClientData` call"
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proc deleteLightClientData*(dag: ChainDAGRef, bid: BlockId) =
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## Delete cached light client data for a given block. This needs to be called
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## when a block becomes unreachable due to finalization of a different fork.
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if dag.lcDataStore.importMode == LightClientDataImportMode.None:
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return
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dag.lcDataStore.cache.data.del bid
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template lazy_header(name: untyped): untyped {.dirty.} =
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## `createLightClientUpdates` helper to lazily load a known block header.
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var
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`name _ ptr`: ptr[BeaconBlockHeader]
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`name _ ok` = true
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template `assign _ name`(target: var BeaconBlockHeader, bid: BlockId): bool =
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if `name _ ptr` != nil:
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target = `name _ ptr`[]
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elif `name _ ok`:
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let bdata = dag.getExistingForkedBlock(bid)
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if bdata.isErr:
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dag.handleUnexpectedLightClientError(bid.slot)
|
|
`name _ ok` = false
|
|
else:
|
|
target = bdata.get.toBeaconBlockHeader()
|
|
`name _ ptr` = addr target
|
|
`name _ ok`
|
|
|
|
template lazy_data(name: untyped): untyped {.dirty.} =
|
|
## `createLightClientUpdates` helper to lazily load cached light client state.
|
|
var `name` {.noinit.}: CachedLightClientData
|
|
`name`.finalized_slot = FAR_FUTURE_SLOT
|
|
template `load _ name`(bid: BlockId) =
|
|
if `name`.finalized_slot == FAR_FUTURE_SLOT:
|
|
`name` = dag.getLightClientData(bid)
|
|
|
|
template lazy_bid(name: untyped): untyped {.dirty.} =
|
|
## `createLightClientUpdates` helper to lazily load a known to exist block id.
|
|
var
|
|
`name` {.noinit.}: BlockId
|
|
`name _ ok` = true
|
|
`name`.slot = FAR_FUTURE_SLOT
|
|
template `load _ name`(slot: Slot): bool =
|
|
if `name _ ok` and `name`.slot == FAR_FUTURE_SLOT:
|
|
let bsi = dag.getExistingBlockIdAtSlot(slot)
|
|
if bsi.isErr:
|
|
dag.handleUnexpectedLightClientError(slot)
|
|
`name _ ok` = false
|
|
else:
|
|
`name` = bsi.get.bid
|
|
`name _ ok`
|
|
|
|
proc createLightClientUpdates(
|
|
dag: ChainDAGRef,
|
|
state: HashedBeaconStateWithSyncCommittee,
|
|
blck: TrustedSignedBeaconBlockWithSyncAggregate,
|
|
parent_bid: BlockId) =
|
|
## Create `LightClientUpdate` instances for a given block and its post-state,
|
|
## and keep track of best / latest ones. Data about the parent block's
|
|
## post-state must be cached (`cacheLightClientData`) before calling this.
|
|
|
|
# Verify sync committee has sufficient participants
|
|
template sync_aggregate(): auto = blck.asSigned().message.body.sync_aggregate
|
|
template sync_committee_bits(): auto = sync_aggregate.sync_committee_bits
|
|
let num_active_participants = countOnes(sync_committee_bits).uint64
|
|
if num_active_participants < MIN_SYNC_COMMITTEE_PARTICIPANTS:
|
|
return
|
|
|
|
# Verify attested block (parent) is recent enough and that state is available
|
|
template attested_bid(): auto = parent_bid
|
|
let attested_slot = attested_bid.slot
|
|
if attested_slot < dag.lcDataStore.cache.tailSlot:
|
|
return
|
|
|
|
# Lazy variables to hold historic data
|
|
lazy_header(attested_header)
|
|
lazy_data(attested_data)
|
|
lazy_bid(finalized_bid)
|
|
lazy_header(finalized_header)
|
|
|
|
# Update latest light client data
|
|
template latest(): auto = dag.lcDataStore.cache.latest
|
|
var
|
|
newFinality = false
|
|
newOptimistic = false
|
|
let
|
|
signature_slot = blck.message.slot
|
|
is_later =
|
|
if attested_slot != latest.attested_header.slot:
|
|
attested_slot > latest.attested_header.slot
|
|
else:
|
|
signature_slot > latest.signature_slot
|
|
if is_later and latest.attested_header.assign_attested_header(attested_bid):
|
|
load_attested_data(attested_bid)
|
|
let finalized_slot = attested_data.finalized_slot
|
|
if finalized_slot == latest.finalized_header.slot:
|
|
latest.finality_branch = attested_data.finality_branch
|
|
elif finalized_slot == GENESIS_SLOT:
|
|
latest.finalized_header.reset()
|
|
latest.finality_branch = attested_data.finality_branch
|
|
elif finalized_slot >= dag.tail.slot and
|
|
load_finalized_bid(finalized_slot) and
|
|
latest.finalized_header.assign_finalized_header(finalized_bid):
|
|
latest.finality_branch = attested_data.finality_branch
|
|
newFinality = true
|
|
else:
|
|
latest.finalized_header.reset()
|
|
latest.finality_branch.reset()
|
|
latest.sync_aggregate = sync_aggregate
|
|
latest.signature_slot = signature_slot
|
|
newOptimistic = true
|
|
|
|
# Track best light client data for current period
|
|
let
|
|
attested_period = attested_slot.sync_committee_period
|
|
signature_period = signature_slot.sync_committee_period
|
|
if attested_period == signature_period:
|
|
template next_sync_committee(): auto = state.data.next_sync_committee
|
|
|
|
let isCommitteeFinalized = dag.isNextSyncCommitteeFinalized(attested_period)
|
|
var best =
|
|
if isCommitteeFinalized:
|
|
dag.lcDataStore.db.getBestUpdate(attested_period)
|
|
else:
|
|
let key = (attested_period, state.syncCommitteeRoot)
|
|
dag.lcDataStore.cache.pendingBest.getOrDefault(key)
|
|
|
|
load_attested_data(attested_bid)
|
|
let
|
|
finalized_slot = attested_data.finalized_slot
|
|
has_finality =
|
|
finalized_slot >= dag.tail.slot and load_finalized_bid(finalized_slot)
|
|
meta = LightClientUpdateMetadata(
|
|
attested_slot: attested_slot,
|
|
finalized_slot: finalized_slot,
|
|
signature_slot: signature_slot,
|
|
has_sync_committee: true,
|
|
has_finality: has_finality,
|
|
num_active_participants: num_active_participants)
|
|
is_better = is_better_data(meta, best.toMeta)
|
|
if is_better and best.attested_header.assign_attested_header(attested_bid):
|
|
best.next_sync_committee = next_sync_committee
|
|
best.next_sync_committee_branch = attested_data.next_sync_committee_branch
|
|
if finalized_slot == best.finalized_header.slot:
|
|
best.finality_branch = attested_data.finality_branch
|
|
elif finalized_slot == GENESIS_SLOT:
|
|
best.finalized_header.reset()
|
|
best.finality_branch = attested_data.finality_branch
|
|
elif has_finality and
|
|
best.finalized_header.assign_finalized_header(finalized_bid):
|
|
best.finality_branch = attested_data.finality_branch
|
|
else:
|
|
best.finalized_header.reset()
|
|
best.finality_branch.reset()
|
|
best.sync_aggregate = sync_aggregate
|
|
best.signature_slot = signature_slot
|
|
|
|
if isCommitteeFinalized:
|
|
dag.lcDataStore.db.putBestUpdate(attested_period, best)
|
|
debug "Best LC update improved", period = attested_period, update = best
|
|
else:
|
|
let key = (attested_period, state.syncCommitteeRoot)
|
|
dag.lcDataStore.cache.pendingBest[key] = best
|
|
debug "Best LC update improved", period = key, update = best
|
|
|
|
if newFinality and dag.lcDataStore.onLightClientFinalityUpdate != nil:
|
|
dag.lcDataStore.onLightClientFinalityUpdate(latest)
|
|
if newOptimistic and dag.lcDataStore.onLightClientOptimisticUpdate != nil:
|
|
dag.lcDataStore.onLightClientOptimisticUpdate(latest.toOptimistic)
|
|
|
|
proc initLightClientDataCache*(dag: ChainDAGRef) =
|
|
## Initialize cached light client data
|
|
if dag.lcDataStore.importMode == LightClientDataImportMode.None:
|
|
return
|
|
|
|
# Prune non-finalized data
|
|
dag.lcDataStore.db.delPeriodsFrom(dag.firstNonFinalizedPeriod)
|
|
|
|
# Initialize tail slot
|
|
let targetTailSlot = dag.targetLightClientTailSlot
|
|
dag.lcDataStore.cache.tailSlot = max(dag.head.slot, targetTailSlot)
|
|
|
|
# Import head state
|
|
if dag.head.slot < dag.lcDataStore.cache.tailSlot:
|
|
return
|
|
withState(dag.headState):
|
|
when stateFork >= BeaconStateFork.Altair:
|
|
dag.cacheLightClientData(state, dag.head.bid)
|
|
else: raiseAssert "Unreachable" # `tailSlot` cannot be before Altair
|
|
if dag.lcDataStore.importMode == LightClientDataImportMode.OnlyNew:
|
|
return
|
|
|
|
# Import light client data for finalized period through finalized head
|
|
let finalizedSlot = max(dag.finalizedHead.blck.slot, targetTailSlot)
|
|
if finalizedSlot >= dag.lcDataStore.cache.tailSlot:
|
|
return
|
|
dag.lcDataStore.cache.tailSlot = finalizedSlot
|
|
let finalizedPeriod = finalizedSlot.sync_committee_period
|
|
var res = dag.initLightClientDataForPeriod(finalizedPeriod)
|
|
|
|
let lightClientStartTick = Moment.now()
|
|
logScope: lightClientDataMaxPeriods = dag.lcDataStore.maxPeriods
|
|
debug "Initializing cached LC data", res
|
|
|
|
# Build list of block to process.
|
|
# As it is slow to load states in descending order,
|
|
# build a reverse todo list to then process them in ascending order
|
|
var
|
|
blocks = newSeqOfCap[BlockId](dag.head.slot - finalizedSlot + 1)
|
|
bid = dag.head.bid
|
|
while bid.slot > finalizedSlot:
|
|
blocks.add bid
|
|
bid = dag.existingParent(bid).valueOr:
|
|
dag.handleUnexpectedLightClientError(bid.slot)
|
|
res.err()
|
|
break
|
|
if bid.slot == finalizedSlot:
|
|
blocks.add bid
|
|
|
|
# Process blocks (reuses `dag.headState`, but restores it to the current head)
|
|
var
|
|
tmpState = assignClone(dag.headState)
|
|
tmpCache, cache: StateCache
|
|
oldCheckpoint: Checkpoint
|
|
cpIndex = 0
|
|
for i in countdown(blocks.high, blocks.low):
|
|
bid = blocks[i]
|
|
if not dag.updateExistingState(
|
|
dag.headState, bid.atSlot, save = false, cache):
|
|
dag.handleUnexpectedLightClientError(bid.slot)
|
|
res.err()
|
|
continue
|
|
let bdata = dag.getExistingForkedBlock(bid).valueOr:
|
|
dag.handleUnexpectedLightClientError(bid.slot)
|
|
res.err()
|
|
continue
|
|
withStateAndBlck(dag.headState, bdata):
|
|
when stateFork >= BeaconStateFork.Altair:
|
|
# Cache light client data (non-finalized blocks may refer to this)
|
|
if i != blocks.low:
|
|
dag.cacheLightClientData(state, bid) # `dag.head` already cached
|
|
|
|
# Create `LightClientUpdate` instances
|
|
if i < blocks.high:
|
|
dag.createLightClientUpdates(state, blck, parentBid = blocks[i + 1])
|
|
else: raiseAssert "Unreachable"
|
|
|
|
let lightClientEndTick = Moment.now()
|
|
debug "Initialized cached LC data",
|
|
initDur = lightClientEndTick - lightClientStartTick, res
|
|
if res.isErr:
|
|
return
|
|
if dag.lcDataStore.importMode == LightClientDataImportMode.OnDemand:
|
|
return
|
|
|
|
# Import historic data
|
|
dag.lcDataStore.cache.tailSlot = targetTailSlot
|
|
let targetTailPeriod = targetTailSlot.sync_committee_period
|
|
if targetTailPeriod < finalizedPeriod:
|
|
# `countdown` through 0 fails on distinct `uint64`
|
|
# https://github.com/nim-lang/Nim/pull/19926
|
|
var period = finalizedPeriod - 1
|
|
while period >= targetTailPeriod:
|
|
if dag.initLightClientDataForPeriod(period).isErr:
|
|
res.err()
|
|
if period <= targetTailPeriod:
|
|
break
|
|
dec period
|
|
debug "Historic LC data imported", res
|
|
|
|
proc processNewBlockForLightClient*(
|
|
dag: ChainDAGRef,
|
|
state: ForkedHashedBeaconState,
|
|
signedBlock: ForkyTrustedSignedBeaconBlock,
|
|
parentBid: BlockId) =
|
|
## Update light client data with information from a new block.
|
|
if dag.lcDataStore.importMode == LightClientDataImportMode.None:
|
|
return
|
|
if signedBlock.message.slot < dag.lcDataStore.cache.tailSlot:
|
|
return
|
|
|
|
when signedBlock is bellatrix.TrustedSignedBeaconBlock:
|
|
dag.cacheLightClientData(state.bellatrixData, signedBlock.toBlockId())
|
|
dag.createLightClientUpdates(state.bellatrixData, signedBlock, parentBid)
|
|
elif signedBlock is altair.TrustedSignedBeaconBlock:
|
|
dag.cacheLightClientData(state.altairData, signedBlock.toBlockId())
|
|
dag.createLightClientUpdates(state.altairData, signedBlock, parentBid)
|
|
elif signedBlock is phase0.TrustedSignedBeaconBlock:
|
|
raiseAssert "Unreachable" # `tailSlot` cannot be before Altair
|
|
else:
|
|
{.error: "Unreachable".}
|
|
|
|
proc processHeadChangeForLightClient*(dag: ChainDAGRef) =
|
|
## Update light client data to account for a new head block.
|
|
## Note that `dag.finalizedHead` is not yet updated when this is called.
|
|
if dag.lcDataStore.importMode == LightClientDataImportMode.None:
|
|
return
|
|
if dag.head.slot < dag.lcDataStore.cache.tailSlot:
|
|
return
|
|
|
|
# Update `bestUpdates` from `pendingBest` to ensure light client data
|
|
# only refers to sync committees as selected by fork choice
|
|
let headPeriod = dag.head.slot.sync_committee_period
|
|
if not dag.isNextSyncCommitteeFinalized(headPeriod):
|
|
let
|
|
tailPeriod = dag.lcDataStore.cache.tailSlot.sync_committee_period
|
|
lowPeriod = max(dag.firstNonFinalizedPeriod, tailPeriod)
|
|
if headPeriod > lowPeriod:
|
|
var tmpState = assignClone(dag.headState)
|
|
for period in lowPeriod ..< headPeriod:
|
|
let
|
|
syncCommitteeRoot =
|
|
dag.syncCommitteeRootForPeriod(tmpState[], period).valueOr:
|
|
dag.handleUnexpectedLightClientError(period.start_slot)
|
|
continue
|
|
key = (period, syncCommitteeRoot)
|
|
dag.lcDataStore.db.putBestUpdate(
|
|
period, dag.lcDataStore.cache.pendingBest.getOrDefault(key))
|
|
withState(dag.headState): # Common case separate to avoid `tmpState` copy
|
|
when stateFork >= BeaconStateFork.Altair:
|
|
let key = (headPeriod, state.syncCommitteeRoot)
|
|
dag.lcDataStore.db.putBestUpdate(
|
|
headPeriod, dag.lcDataStore.cache.pendingBest.getOrDefault(key))
|
|
else: raiseAssert "Unreachable" # `tailSlot` cannot be before Altair
|
|
|
|
proc processFinalizationForLightClient*(
|
|
dag: ChainDAGRef, oldFinalizedHead: BlockSlot) =
|
|
## Prune cached data that is no longer useful for creating future
|
|
## `LightClientUpdate` and `LightClientBootstrap` instances.
|
|
## This needs to be called whenever `finalized_checkpoint` changes.
|
|
if dag.lcDataStore.importMode == LightClientDataImportMode.None:
|
|
return
|
|
let finalizedSlot = dag.finalizedHead.slot
|
|
if finalizedSlot < dag.lcDataStore.cache.tailSlot:
|
|
return
|
|
|
|
# Cache `LightClientBootstrap` for newly finalized epoch boundary blocks
|
|
let
|
|
firstNewSlot = oldFinalizedHead.slot + 1
|
|
lowSlot = max(firstNewSlot, dag.lcDataStore.cache.tailSlot)
|
|
var boundarySlot = finalizedSlot
|
|
while boundarySlot >= lowSlot:
|
|
let
|
|
bsi = dag.getExistingBlockIdAtSlot(boundarySlot).valueOr:
|
|
dag.handleUnexpectedLightClientError(boundarySlot)
|
|
break
|
|
bid = bsi.bid
|
|
if bid.slot >= lowSlot:
|
|
dag.lcDataStore.db.putCurrentSyncCommitteeBranch(
|
|
bid.slot, dag.getLightClientData(bid).current_sync_committee_branch)
|
|
boundarySlot = bid.slot.nextEpochBoundarySlot
|
|
if boundarySlot < SLOTS_PER_EPOCH:
|
|
break
|
|
boundarySlot -= SLOTS_PER_EPOCH
|
|
|
|
# Seal sync committee periods for which data can no longer improve further
|
|
let
|
|
oldFinalizedPeriod = oldFinalizedHead.slot.sync_committee_period
|
|
newFinalizedPeriod = dag.finalizedHead.slot.sync_committee_period
|
|
if newFinalizedPeriod > oldFinalizedPeriod:
|
|
for period in countdown(newFinalizedPeriod - 1, oldFinalizedPeriod):
|
|
if dag.lcDataStore.cache.tailSlot > period.start_slot:
|
|
break
|
|
debug "Best LC update sealed",
|
|
period, update = dag.lcDataStore.db.getBestUpdate(period)
|
|
dag.lcDataStore.db.sealPeriod(period)
|
|
|
|
# Prune light client data that is no longer referrable by future updates
|
|
var bidsToDelete: seq[BlockId]
|
|
for bid, data in dag.lcDataStore.cache.data:
|
|
if bid.slot >= dag.finalizedHead.blck.slot:
|
|
continue
|
|
bidsToDelete.add bid
|
|
for bid in bidsToDelete:
|
|
dag.lcDataStore.cache.data.del bid
|
|
|
|
# Prune seal tracking data that is no longer relevant
|
|
let targetTailPeriod = dag.targetLightClientTailSlot.sync_committee_period
|
|
dag.lcDataStore.db.keepPeriodsFrom(targetTailPeriod)
|
|
|
|
# Prune best `LightClientUpdate` referring to non-finalized sync committees
|
|
# that are no longer relevant, i.e., orphaned or too old
|
|
let firstNonFinalizedPeriod = dag.firstNonFinalizedPeriod
|
|
var keysToDelete: seq[(SyncCommitteePeriod, Eth2Digest)]
|
|
for (period, committeeRoot) in dag.lcDataStore.cache.pendingBest.keys:
|
|
if period < firstNonFinalizedPeriod:
|
|
keysToDelete.add (period, committeeRoot)
|
|
for key in keysToDelete:
|
|
dag.lcDataStore.cache.pendingBest.del key
|
|
|
|
proc getLightClientBootstrap*(
|
|
dag: ChainDAGRef,
|
|
blockRoot: Eth2Digest): Opt[altair.LightClientBootstrap] =
|
|
if not dag.lcDataStore.serve:
|
|
return err()
|
|
|
|
let bdata = dag.getForkedBlock(blockRoot).valueOr:
|
|
debug "LC bootstrap unavailable: Block not found", blockRoot
|
|
return err()
|
|
|
|
withBlck(bdata):
|
|
let slot = blck.message.slot
|
|
when stateFork >= BeaconStateFork.Altair:
|
|
if slot < dag.targetLightClientTailSlot:
|
|
debug "LC bootstrap unavailable: Block too old", slot
|
|
return err()
|
|
if slot > dag.finalizedHead.blck.slot:
|
|
debug "LC bootstrap unavailable: Not finalized", blockRoot
|
|
return err()
|
|
var branch = dag.lcDataStore.db.getCurrentSyncCommitteeBranch(slot)
|
|
if branch.isZeroMemory:
|
|
if dag.lcDataStore.importMode == LightClientDataImportMode.OnDemand:
|
|
let bsi = ? dag.getExistingBlockIdAtSlot(slot)
|
|
var tmpState = assignClone(dag.headState)
|
|
dag.withUpdatedExistingState(tmpState[], bsi) do:
|
|
branch = withState(state):
|
|
when stateFork >= BeaconStateFork.Altair:
|
|
state.data.build_proof(altair.CURRENT_SYNC_COMMITTEE_INDEX).get
|
|
else: raiseAssert "Unreachable"
|
|
do: return err()
|
|
dag.lcDataStore.db.putCurrentSyncCommitteeBranch(slot, branch)
|
|
else:
|
|
debug "LC bootstrap unavailable: Data not cached", slot
|
|
return err()
|
|
|
|
let period = slot.sync_committee_period
|
|
var tmpState = assignClone(dag.headState)
|
|
var bootstrap {.noinit.}: altair.LightClientBootstrap
|
|
bootstrap.header =
|
|
blck.toBeaconBlockHeader()
|
|
bootstrap.current_sync_committee =
|
|
? dag.existingCurrentSyncCommitteeForPeriod(tmpState[], period)
|
|
bootstrap.current_sync_committee_branch =
|
|
branch
|
|
return ok bootstrap
|
|
else:
|
|
debug "LC bootstrap unavailable: Block before Altair", slot
|
|
return err()
|
|
|
|
proc getLightClientUpdateForPeriod*(
|
|
dag: ChainDAGRef,
|
|
period: SyncCommitteePeriod): Option[altair.LightClientUpdate] =
|
|
if not dag.lcDataStore.serve:
|
|
return
|
|
|
|
if dag.lcDataStore.importMode == LightClientDataImportMode.OnDemand:
|
|
if dag.initLightClientUpdateForPeriod(period).isErr:
|
|
return
|
|
result = some(dag.lcDataStore.db.getBestUpdate(period))
|
|
let numParticipants = countOnes(result.get.sync_aggregate.sync_committee_bits)
|
|
if numParticipants < MIN_SYNC_COMMITTEE_PARTICIPANTS:
|
|
result.reset()
|
|
|
|
proc getLightClientFinalityUpdate*(
|
|
dag: ChainDAGRef): Option[altair.LightClientFinalityUpdate] =
|
|
if not dag.lcDataStore.serve:
|
|
return
|
|
|
|
result = some(dag.lcDataStore.cache.latest)
|
|
let numParticipants = countOnes(result.get.sync_aggregate.sync_committee_bits)
|
|
if numParticipants < MIN_SYNC_COMMITTEE_PARTICIPANTS:
|
|
result.reset()
|
|
|
|
proc getLightClientOptimisticUpdate*(
|
|
dag: ChainDAGRef): Option[altair.LightClientOptimisticUpdate] =
|
|
if not dag.lcDataStore.serve:
|
|
return
|
|
|
|
result = some(dag.lcDataStore.cache.latest.toOptimistic)
|
|
let numParticipants = countOnes(result.get.sync_aggregate.sync_committee_bits)
|
|
if numParticipants < MIN_SYNC_COMMITTEE_PARTICIPANTS:
|
|
result.reset()
|